cbr 600 fj 1988?

Question

Hi. Is there an experianced motorctcle machanic who could give me some advise on this problem. Or better still. Lives near guildford that can sort the problem out at cost. The problem goes like this. It starts up ok. Tick over not all that. But wen i go to pull away. The revs drop and the bike then has to pick pick up speed to get going. And on top of this. The bike has no pwer or revs in the higher gears. For instance. The bike will not do over 60 mph and will not go over 8000 revs. But if i race it though the gears it will get to 90 mph and 10,000 revs in 5th gear. But as soon as i put it into 6th. the revs drop back to 6000 and the the speed drops to betwwen 60 and 70.

Answer 1

The bike is old enough to need top end work.
Cylinder bore, piston & rings.
Do a compression test.
Also the valves could be leaking due to carbon build up and constant pounding into the valve seats.
First try adjusting the valves.
Then perform a cylinder "leak down" test to check for valve leakage.

Answer 2

it is totally pretty much 2 many years previous. it could want a valve interest. Carbon builds up between the valve faces and valve seats. that stops them from making a good seal and a few compression is lost, lowering HP. alter the valves. whilst checking the clearances - in the event that they are loose, it is because of the fact the carbon construction up is retaining them open. in the event that they are tight, it is because of the fact the valve faces, seats and stems are turning out to be worn down. Tight valve clearances are retaining the valves open, which lead them to leak and loose HP. carry out a cylinder "leak down" attempt to learn for valve leakage. examine the cylinder compression collectively as your at it.

Answer 3

Try a new set of spark plugs. my cbr looses power when they are getting ready for a change.

Answer 4

hard to tell, but is probably carburetor related... try comparing the exhaust temps from each pipe.. & of course, pull the plugs & take a look....